1. Field of the Invention
This invention relates to an improvement applicable to a tool exchange or replacement system for a machining tool. More specifically, this invention relates to an improvement applicable to a tool exchange or replacement system for a machining tool for the purpose of prohibiting any mutual disturbance from occurring between a work to be machined and any tool which is mounted on a magazine of the machine tool in the vicinity of the tool presently employed or between the work to be machined and any part of the machine tool, thereby an operator of the machine tool is given a wide space for operation of the machine tool.
2. Description of the Related Art
Presently available are a variety of tool exchange or replacement systems each of which has a magazine on which a plurality of tools are mounted to be selectively employed.
The inventors of the present invention were successful in development of such a tool exchange or replacement system for machine tools as was mentioned above, and filed an application for patent (PCT/JP82/00367). FIGS. 1 and 2 show one embodiment of the above mentioned tool exchange or replacement system for machine tools, illustrated respectively in one position in which a tool 8 is coupled with a main spindle 5 and is kept apart from a magazine 9. Each piece of the bevel gears 20 and 21 is uncoupled from each other to allow machining and in the other position in which the tool 8 is not coupled with the main spindle 5 but is mounted on the magazine and each piece of the bevel gears 20 and 21 are coupled to each other to allow a tool to be exchanged or replaced by another.
Referring to the drawings, this tool exchange or replacement system developed by the inventors of this invention and which is available in the prior art, provides a piece of bevel gear 20 supported by the end of a main spindle 5 rotatably supported by a spindle head 4, a magazine 9 movable along the spindle head 4 in the vertical direction and which holds a plurality of tools 8, and the other piece of bevel gear 21 supported by the magazine 9 and which couples with the aforementioned piece of bevel gear 20 at the upper end position of the stroke of the spindle head 4.
After a machining operation finishes at the position illustrated in FIG. 1, the tool 8 employed for the finished machining is replaced by another tool 8, by unclamping the used tool 8 from the main spindle 5 by employing a tool attachment/removal means (not shown) such as a drawbar, etc, and by lifting the spindle head 4 which rotatably houses the main spindle 5 to the position illustrated in FIG. 2, with the magazine 9 remaining at the position illustrated in FIG. 1. This upward move of the spindle head 4 causes the used tool 8 which was already unclamped from the main spindle 5 during the aforementioned step, to be drawn out of the main spindle 5. The upward move of the spindle head 4, incidentally, causes the bevel gears 20 and 21 to be mutually coupled. Then, the main spindle 5 is rotated to rotate the bevel gears 20 and 21 which rotate the magazine 9, until another tool 8 which will be employed for the next machining operation meets the main spindle 5 during this rotation step. The tool 8 which was employed in the last machining operation moves to another position at which it does not meet the main spindle 5, before lowering the spindle head 4 along the magazine 9 until the aforementioned bevel gears 20 and 21 are uncoupled and the newly selected tool 8 is clamped with the main spindle 5 by employing the tool attachment/removal means (not shown), such as a drawbar, etc., to return to the machining position illustrated in FIG. 1.
At the machining position illustrated in FIG. 1, one of the tool holders of the magazine 9 stays close to the lower end of the main spindle 5. Since the tool holders of the magazine 9 are not connected with the main spindle 5, but surrounds the main spindle 5, however, the rotation of the main spindle 5 causes the tool 8 alone to rotate, readily allowing an operator of the machine tool to conduct various operation around the location close to the work (not shown) to be machined and the lower end of the main spindle 5 however, the tools 8 mounted on the tool holders (not shown) located adjacent to the tool holder facing the main spindle 5, causes some disturbance thereto.
The aforementioned tool exchange or replacement system needs no drive which is employed exclusively for exchanging or replacing tools, because a drive for driving a main spindle is employed also for rotating the magazine for indexing a tool. As a result, the structure thereof is simple and the tool exchange or replacement system is convenient particularly from the practical viewpoints.
The aforementioned tool exchange or replacement system which is illustrated in FIG. 1, allows one of the tool holders of the magazine to remain surrounding the lower end of the main spindle, resultantly disturbing the operator in his work in the neighborhood of the machining area. Further, some of the tool holders of the magazine located adjacent to the above mentioned one also disturbs the operator in his work in the vicinity of the machining area.